Forecast: First Call For February 11th-12th
First off, my confidence level in my forecast first call:
Had I not seen the 6z data (which is released between 3 and 5 AM), I would have a higher number thrown out there on both sides of the line (9/6 perhaps). The 6z data pushes this storm further east. While normally I disregard the off-run data (off-run being model runs at 6 and 18z (1 AM and 1 PM) as little more than additional guidance, considering how close we are to the storm I don't want to be too confident in my thinking yet.
As you can see there is a huge difference in the track from last night to the early morning run. If this east trend continues later today, I will revise my accumulations dramatically. This by no means is set in stone. Hence the numbers assigned for confidence are not higher than I would like them to be.
Timing: The event should start between 1 and 3 PM in Philadelphia, 2 and 4 PM north. Event should last into the overnight hours Saturday night and Sunday.
Expect: Increasing winds throughout the afternoon. Snow and possibly a mix with sleet and rain (especially south and east) to break out at first with precip changing to snow across the area by early evening. The faster the low bombs out, the stronger the winds will be and perhaps, the higher potential for snow and even thundersnow in places.
A second and final call will be issued by late this afternoon. I will have 'Tracking the Event' running by 9 AM on Saturday, so you can watch the precip move into the area and watch the storm develop.
Had I not seen the 6z data (which is released between 3 and 5 AM), I would have a higher number thrown out there on both sides of the line (9/6 perhaps). The 6z data pushes this storm further east. While normally I disregard the off-run data (off-run being model runs at 6 and 18z (1 AM and 1 PM) as little more than additional guidance, considering how close we are to the storm I don't want to be too confident in my thinking yet.
As you can see there is a huge difference in the track from last night to the early morning run. If this east trend continues later today, I will revise my accumulations dramatically. This by no means is set in stone. Hence the numbers assigned for confidence are not higher than I would like them to be.
Timing: The event should start between 1 and 3 PM in Philadelphia, 2 and 4 PM north. Event should last into the overnight hours Saturday night and Sunday.
Expect: Increasing winds throughout the afternoon. Snow and possibly a mix with sleet and rain (especially south and east) to break out at first with precip changing to snow across the area by early evening. The faster the low bombs out, the stronger the winds will be and perhaps, the higher potential for snow and even thundersnow in places.
A second and final call will be issued by late this afternoon. I will have 'Tracking the Event' running by 9 AM on Saturday, so you can watch the precip move into the area and watch the storm develop.
